Nongxiangxing baijiu (NXXB) is one of the main types of Chinese Baijiu. Its unique flavor is formed during fermentation by the combined action of various microorganisms, with lactic acid bacteria (LAB) making a great contribution. Lactate fermentation produces the precursors of key flavor compounds, such as lactic acid, acetic acid, and other flavor compounds, which combine to produce the unique sensory characteristics of NXXB. This review focuses on the diversity of LAB species and their physiological and metabolic characteristics. These characteristics include key species involved at different fermentation stages, metabolite biosynthesis, acid-tolerance mechanisms, interactions with yeasts, and factors influencing LAB community composition. It also discusses current challenges and future research directions for LAB in relation to NXXB production, aiming to advance understanding and potential future applications of these bacteria.